Certain 2-alkoxymethyl-3-chloro-delta 3-1,2,4-thiadiazolin-5-ones and their preparation

ABSTRACT

2-Alkoxymethyl-3-chloro- Delta 3-1,2,4-thiadiozolin-5-ones are obtained when a carbodiimide of the formula

United States Patent 1 396919184 Fischer 1 Sept. 12, 1972 CERTAIN 2-ALKOXYMETHYL-3- CHLORO-A 3-l,2,4-THIADIAZOLIN-5- Primary Examiner-Alex Mazel ONES AND THEIR PREPARATION Assistant Examiner-R. J. Gallagher [72] Inventor: Peter Fischer, Odenthal-Osenau, Attorney-BurgessDmklage & sprung Germany [57] ABSTRACT [73] Asstgnee: Farbenfabriken Bayer Aktiengeseuschafl, Leverkusen, 2-Alkoxymethyl-3-chloro-A -l,2,4-th1ad1ozol1n-5-ones many are obtained when a carbodiimide of the formula [22] Filed: May 18, 1970 ROCH N C N-CH,OR,

[21] Appl. No.: 38,577 in which R is an aliphatic radical, is reacted with chlorocarbonylsulphenyl chloride in the presence of 30 Ford n A H ti D m an inert, organic diluent in the temperature range of l l g pp ca on y a 0 to 100 C and the diluent and the chloromethylalkyl y 21, 1969 Germany 19 25 995-1 ether liberated on heating are removed at a temperature in the re ion of 50 to 120C. The new com- [52] US. Cl. ..260/302 D, 71/90, 260/566 R pounds are Seal as herbicides [51] Int. Cl. ..C07d 91/60 [58] Field of Search ..260/302 D 15 Claims, No Drawings CERTAIN 2-ALKOXYMETHYL-3-CHLORO-A 3- 1,2,4-THIADlAZOLIN-5-ONES AND THEIR PREPARATION The invention relates to new 2-alkoxymethyl-3- chloro-A -l ,2,4-thiadiazo1in 5-ones and to a process for their preparation.

It has been found that a 2-a1kyloxymethy1-3-chloro-A 3 -1,2,4-thiadiazo1in 5-ones is obtained when a carbodiimide of the formula:

in which R is an aliphatic radical, is reacted with chlorocarbonylsulphenyl chloride in the presence of an inert, organic diluent in the temperature range of 0 to 100C and the diluent and the chloromethylalkyl ether liberated on heating are then removed at a temperature in the region of 50 to about 120 C.

The reactants are generally used in approximately the stoichiometric ratios although chlorocarbonylsulphenyl chloride may be used in an excess of up to about percent if desired. In this case the excess chlorocarbonylsulphenylchloride may then be removed by distillation together with the solvent and the chloromethylalkylether liberated in the reaction.

The reaction is preferablycarried out in a temperature range of 20 to 90C.

The aliphatic radicals are straight chained and optionally branched alkyl radicals having from one to eight and preferably from one to four carbon atoms. Cycloalkyl radicals having from five to 12 and preferably five to six carbon atoms in the ring system are, of course, also understood to be aliphatic radicals. Examples of aliphatic radicals are methyl, ethyl, npropyl, i-propyl, n-butyl and the tertiary butyl or noctyl radical as well as the cyclopentyl and cyclohexyl radical.

The carbodiimides used for the process may be prepared by the known methods, for example by condensation of the corresponding isocyanates with liberation of CO in the presence of a phosphorus catalyst. Chlorocarbonyl sulphenyl chloride is a known compound.

The following are mentioned as examples of carbodiimide's which may be used for the process: Bis- (methoxymethyl)-carbodiimide; bis-(ethoxymethy1)- carbodiimide; bis-(N-propoxymethyl)-carbodiimide; bis-(isobutoxymethyl)-carbodiimide, bis(cyc1opentyloxymethyl)-carbodiimide; bis-(cyclohexyloxymethyl)-carbodiimide and bis-(n-octyloxymethy1)- carbodiimide.

Suitable diluents for the process are, for example, hydrocarbons and chlorinated hydrocarbons such as hexane, benzene, toluene, chlorobenzene, carbon tetrachloride or chloroform. The removal of the solvents which have a boiling point above 100C. being carried out at reduced pressure within the given temperature range of about 50 to about 120C.

The process will now be explained with the aid of the following Example:

The reaction mixture is processes in the conventional manner. The new compound remaining behind as a residue which is isolated in the conventional manner by distillation at a reduced pressure or by extraction with a low boiling, optionally chlorinated hydrocarbon such as hexane or chloroform, and it may be purified by recrystallization.

The new compounds correspond to the general formula EXAMPLE g. of chlorocarbonylsulphenyl chloride are added to 30 g. of bis-(methoxymethyl)-carbodiimide, b.p.

60C/4 mm. Hg, in 300 ml. of benzene, and the reaction mixture is boiled for one-half hour and processed by distillation. I

Yield: 30 g. of 2-methoxymethyl-3-chloro-A-1,2,4- thiadiazolin-S-ones, b.p. -84C/0.2-0.3 mm Hg; solidification point 458C.

' Analysis: (Molecular weight 180.6)

0 N 8 Calculated: 26.6% 2.79% 17.7% 15.6% 17.8% 19.6% Found: 26.5% 2.8% 18.1% 16.0% 111.2% 19.1%

The following 2-alkoxymethyl-3-ch1oro-A- 1 ,2,4-

thiadiazolin-S-ones may be obtained in an analogous manner:

MoLwt.

Alkyl Bp/mm HgS.P, cal- N S Cl C culated found: N 8 Cl Mol.w1. Ethyl /0.6 42.6 14.4 18.1 194.5

14.2 18.3 n-Propyl 90/0.2 13.4 15.4 17.0 208.5

14.1 15.4 16.7 216 i-Propyl 85"/0.1 13.4 15.4 17.0 208.5

13.5 14.8 16.1 208 n-Butyl l0.3 12.6 14.4 15.9 222.7

12.8 14.4 15.5 223 i-Butyl /0.5 12.6 14.4 15.9 222.7

12.7 14.5 15.3 216 n-Octyl 10.0 11.3 12.7 278.9

9.8 10.5 11.9 269 0 5 Cl Mol.wt Cyclohexyl 12.9 12.9 14.3 248.7

Preparations purified by thin layer chromatography.

alkyl= millet beet oats cotton wheat mustard beans methyl 3 5 3 4 2 4-5 2 i-propyl 3 5 2 0 3 S 2 n-butyl 2 3 l 0 4 5 3 i-butyl 3 5 3 n-octyl 4 4 obtained in a similar manner from the corresponding isocyanates Alkyl ethyl b.p. 68C/0.5 mm Hg. n-Propyl b.p. 87C/0.2 mm Hg. n-Butyl b.p. 80C/0.l mm Hg. i-Butyl b.p. 80C/0.l mm Hg. n-Octyl b.p. l60C/0.3 mm Hg.

b. Preparation of the isocyanate 490 g. of isopropyl chloromethylether and 132 g. of benzyl cyanide dissolved in 550 g. of a hydrocarbon fraction which boils at 190 to 210C. are reacted with 530 g. of sodium cyanate at a temperature in the range of 100 to 120C. After 7 hours, a filtered sample is found to contain only traces of chlorine. After cooling, the reaction mixture is filtered and fractionated. Yield: 340 g. of isopropoxymethylisocyanate, b.p. 65C/ 104 mm Hg.

The following compounds are obtained in a similar manner (see British Pat. No. 1,104,917 and 1.1.8. Patent No. 3,453,310) from the corresponding alkyl chloromethylethers by reacting them with sodium cyanate in a mixture of a polar and a non-polar solvent:

Ethoxymethylisocyanate b.p. 108C/760 mm Hg. n-Propoxymethylisocyanate b.p. 80 C/l44 mm Hg. lsobutoxymethylisocyanate b.p. 66C/50 mm Hg. n-Octyloxymethylisocyanate b.p. 70C] 0.5 mm Hg. Cyclohexyloxymethylisocyanate b.p. 100C/27 mm Hg.

c. Chloromethylether Hydrogen chloride is introduced to saturation point into a solution of 270 g. of trioxane, 540 g. of

isopropanol and 500 g. of benzene, the reaction mixn-Propylchloromethyl ether lsobutylchloromethylether C yclohexylchloromethylether b.p. 50C/l mm Hg. b.p. 105C/ 60 mm Hg. b.p. 43Cl0.3 mm Hg.

What we claim is: 1. 2-Alk0xymethyl-3-chloro-A -1,2,4-thiadiazolin-5- ones of the formula wherein R is selected from the group consisting of alkyl with up to eight carbon atoms and cycloalkyl with five to 12 carbon atoms in the ring system.

2. Compounds according to claim 1 in which R is an aliphatic radical selected from the group consisting of alkyl with up to four carbon atoms and cycloalkyl with five or six carbon atoms in the ring system.

3. A -1,2,4-thiadiazolin-5-ones according to claim 1 wherein R is selected from the group consisting of ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-octyl, and cyclohexyl.

4. Compound according to claim 1:

2-Ethoxymethyl-3-chloro-A -1 ,2,4-thiadiazolin-5- one.

5. Compound according to claim 1:

2-n-Propoxymethy1-3-chloro-A 1 ,2 ,4-thiadiazolin-rone.

6. Compound according to claim 1:

2-lsopropoxymethyl-3-chloro-A -l ,2,4-thiadiazolin- 5-one.

7. Compound according to claim 1:

Z-n-Butoxymethyl-El-chloroA l ,2,4-thiadiazolin-5- one.

8. Compound according to claim 1:

2-lso-butoxymethy1-3-chloro-A-1,2,4-thiadiazolin- 5-one.

9. Compound according to claim 1:

2-n-Octyloxymethyl-3-ch1oro-A -1,2,4-thiadiazolin- S-one.

10. Compound according to claim 1:

2-Cyclohexyloxymethyl-3-chloro-A -1,2,4-

thiadiazolin-S-one.

11. A process for the preparation of a 2-alkoxymethyl-3-chloro-A -1,2,4-thiadiazolin-5-ones, wherein a carbodiimide of the formula wherein R is selected from the group consisting of alkyl with up to eight carbon atoms and cycloalkyl with five to 12 carbon atoms in the ring system, is reacted with chlorocarbonylsulphenylchloride in the presence of an inert organic diluent at a temperature in the range of from 0 to C, and wherein the diluent and chloromethylalkylether which is liberated on heating are removed at a temperature in the range of from 50 to C. 12. A process according to claim 11, wherein the aliphatic radical contains from one to 12 carbon atoms. 13. A process according to claim 11, wherein the chlorocarbonyl sulphonyl chloride is used in an excess of up to 20 percent based on the stoichiometric ratio, and wherein this excess is removed by distillation together with the solvent and the chloromethylalkylether liberated in the reaction.

14. A process according to claim 11, wherein the inert organic diluent is a hydrocarbon.

15. A process according to claim 11, wherein the carbodiimide is bis-(methoxymethyl)-carbodiimide. 

2. Compounds according to claim 1 in which R1 is an aliphatic radical selected from the group consisting of alkyl with up to four carbon atoms and cycloalkyl with five or six carbon atoms in the ring system.
 3. Delta 3-1,2,4-thiadiazolin-5-ones according to claim 1 wherein R1 is selected from the group consisting of ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-octyl, and cyclohexyl.
 4. CompoUnd according to claim 1: 2-Ethoxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-one.
 5. Compound according to claim 1: 2-n-Propoxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-r-one.
 6. Compound according to claim 1: 2-Isopropoxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-one.
 7. Compound according to claim 1: 2-n-Butoxymethyl-3-chloro Delta 3 -1,2,4-thiadiazolin-5-one.
 8. Compound according to claim 1: 2-Iso-butoxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-one.
 9. Compound according to claim 1: 2-n-Octyloxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-one.
 10. Compound according to claim 1: 2-Cyclohexyloxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-one.
 11. A process for the preparation of a 2-alkoxymethyl-3-chloro- Delta 3-1,2,4-thiadiazolin-5-ones, wherein a carbodiimide of the formula R1O-CH2-N=C=N-CH2-OR1, wherein R1 is selected from the group consisting of alkyl with up to eight carbon atoms and cycloalkyl with five to 12 carbon atoms in the ring system, is reacted with chlorocarbonylsulphenylchloride in the presence of an inert organic diluent at a temperature in the range of from 0* to 100*C, and wherein the diluent and chloromethylalkylether which is liberated on heating are removed at a temperature in the range of from 50* to 120*C.
 12. A process according to claim 11, wherein the aliphatic radical contains from one to 12 carbon atoms.
 13. A process according to claim 11, wherein the chlorocarbonyl sulphonyl chloride is used in an excess of up to 20 percent based on the stoichiometric ratio, and wherein this excess is removed by distillation together with the solvent and the chloromethylalkylether liberated in the reaction.
 14. A process according to claim 11, wherein the inert organic diluent is a hydrocarbon.
 15. A process according to claim 11, wherein the carbodiimide is bis-(methoxymethyl)-carbodiimide. 